Impact of Intraoperative Nanocarbon Staining and parathyroid autotransplantation on parathyroid injury and recovery in adult thyroidectomy: a retrospective cohort study

Thyroid surgeries are intricate operations that carry the risk of damaging the parathyroid glands, which can result in hypocalcemia and potential long-term hypoparathyroidism. Innovative surgical techniques including Intraoperative Nanocarbon Staining (INS), aim to enhance the preservation of parathyroid glands. This study assesses the effectiveness of INS combined with parathyroid autotransplantation in reducing postoperative complications and preserving parathyroid function.

This retrospective cohort study assessed patients aged ≥ 18 who underwent thyroid surgery at a tertiary care hospital from January 2017 to December 2022. We compared the incidence of postoperative parathyroid injury, recovery rates of parathyroid function, and the incidence of permanent hypoparathyroidism between groups. Data on patient demographics, diagnosis, surgical details, parathyroid hormone levels, and calcium levels were collected and analyzed using chi-square tests, t-tests, and logistic regression.

The study included 198 patients, with 101 in the intervention group and 97 in the control group. Baseline characteristics such as sex ratio, age, BMI, and preoperative calcium levels showed no significant differences between groups. The intervention group demonstrated a significantly shorter duration of intravenous calcium supplementation (median 2 vs. 3 days, p < 0.001) and higher calcium nadir levels (median 8.36 vs. 7.85 mg/dL, p < 0.001) compared to controls. Furthermore, the incidence of postoperative parathyroid injury and permanent hypoparathyroidism was lower in the intervention group (15.84% vs. 20.62%, p = 0.045 and 4.95% vs. 15.46%, p = 0.003, respectively). Multivariate analysis revealed factors such as Blood iPTH monitoring level (OR 1.053, 95% CI 1.009–1.099, P = 0.018) and surgery type (Near Total Thyroidectomy) (OR 0.447, 95% CI 0.202–0.990, P = 0.047) were positively associated with surgical success. The intervention group also showed higher surgery success rates (OR 2.054, 95% CI 1.017–4.150, P = 0.045).

The application of INS and parathyroid autotransplantation during thyroidectomy significantly improves postoperative parathyroid gland function, reducing the incidence of permanent hypoparathyroidism. These findings support the incorporation of these techniques into standard surgical practice for thyroidectomy.